Mineral oil compositions



trials MINERAL OIL COMPOSITIONS Thoburn P. Sands, Maplewood, Mo.,assignor to Monsanto Chemical Company, St. Louis, Mo., a corporation ofDelaware No Drawing. Application May 7, 1954 Serial No. 428,389

14 Claims. (Cl. 252-334) This invention relates to improvements inmineral oil lubricating compositions.

Many oil-soluble additives have been proposed for the purpose ofimparting detergent-dispersant properties and oxidation inhibitingproperties to mineral oil fractions employed as lubricating oils. Inthat no one substance satisfactorily imparts both oxidation inhibitingand detergent-dispersant properties to a mineral oil lubricatingfraction various combinations of oil-soluble additives have beenproposed and while some combinations are satisfactory the art hasconstantly sought improvements particularly with respect to the moreefficient and more economical use of such additives.

Among the more effective additives imparting detergent-dispersantproperties to mineral oil lubricating fractions are the oil-solublemetallo hydrocarbon sulfonates, particularly the oil-soluble metallowax-alkylated aryl sulfonates. However, these detergents tend toincrease the oxidation rate ofthe oil during use and their presenceresults in an increased concentration of acidic oxidation products inthe oil. The increase in the amounts of these acidic oxidation productspresents a serious corrosion problem particularly in internal combustionengines which employ alloy bearings. Antioxidants or oxidationinhibiting agents have been added to mineral oil lubricatingcompositions to prevent or inhibit the formation of mineral oiloxidation products and among the antioxidants proposed for use with themetallo hydrocarbon sulfonate detergent-dispersants are the expensiveoil-soluble sul-' fit of their individual properties is not realized.

In accordance with this invention it has been found that thedetergent-dispersant and oxidation characteristics of a mineral oilfraction of lubricating viscosity containing a minor proportion of amixture of an oil-soluble phosphorizedand sulfurized-dicyclic terpeneantioxidant and an'oil-soluble metallo hydrocarbon sulfonatedetergent-dispersant is materially improved by incorporating therein asmall amount of an oil-soluble sulfurized-monocyclic terpene.Furthermore a more stable and more economical mineral oil lubricatingcomposition is obtained by the incorporation in a mineral oil containinga detergent-dispersant and an antioxidant of the aforesaid types .asmall amount of a sulfurized-monocyclic terpene.

The amount of oil-soluble sulfurized-monocyclic terpene added to amineral oil fraction containing an oilsoluble phosphorizedandsulfurized-dicyclic terpene antioxidant and an oil-soluble metallohydrocarbon sulfonate detergent dspersant in order to provide a morestable, more efii ient and more economical lubricating composi- .tionwill vary depending upon the circumstances, such as -lubr catmgcompositions were prepared and evalnated for example the character ofthe mineral oil fraction, the concentrations and type of phosphorizedandsulfurizeddicyclic terpene antioxidant and metallo hydrocarbon sul-'fonate detergent-dispersant, the proposed use of the lubri eatingcomposition, and the like; In general the concentrations by weight withrespect to the oil base will be 0.l-10% of the metallo hydrocarbonsulfonate detergent-dispersant, ODS-3% of the phosphorizedandsulfurized-dicyclic terpene antioxidant and 0.05-2% of thesulfurized-monocyclic terpene, however, concentrations of the order of0.45% by weight of the. sulfonate detergent-dispersant, 0.l-1% of thephosphorizedand sulfurized-dicyclic terpene, and 0.10.5% of thesulfurizedmonocyclic terpene with respect to the mineral oil fractionprovide a highly efficient and economical lubricating oil compositionwhich is satisfactory for most purposes. A particularly effective andeconomical lubricating composition is one containing predominantly amineral oil fraction of lubricating viscosity and with respect to theoil base 0.2-0.4% by weight of an oilsoluble sulfurizedmonocyclicterpene, 0.2-0.4% by weight of an oil-soluble phosphorizedandsulfurized-dicyclic terpene, and 0.6-- 1.2% of an oil-soluble di-waxalkylated benzene sulfonate of an alkaline earth metal such asmagnesium, calcium, strontium, or barium. For purposes of this inventionmagnesium is includedin the alkaline earth metal group.

In general a given quantity of a sulfurized monocyclic terpene of thisinvention upon its incorporation in a lubricating oil compositioncontaining a phosphorizedand sulfurized-dicyclic terpene antioxidant anda metallo hydrocarbon sulfonate detergent-dispersant in effect isequivalent to the incorporation in the oil of approximately an equalweight of a phosphorizedand sulfurized-dicyclic terpene antioxidant andfrom approximately an equal weight to as much as four to five times itsweight of a -:and sulfurized-dic'yclic terpene antioxidant and themetallo hydrocarbon sulfonate detergent-dispersant are necessary toprovide a highly satisfactory and relatively inexpensive lubricatingoil. To give a specific example the following lubricating mineral oilcompositions were prepared and evaluated by the Coordinating ResearchCouncil L-4-'545 and L-1-545 tests and found to exhibit substantiallythe same oxidation stability and detergent-dispersant properties.

Lubricant Composition A B Parts by Parts by weight weight Mineral Oil ofLubricating Viscosity 88. 25 88, Basic Barium Salt of a Di-wax-alkylated4 Bevene Sulfonic Acid (16.1% Barium; 1 3.87% Sulfu 1.63 0.65Phosphorizedand Sulfurized-Pinene (7.7%

Pho phorus. 21.3% Sulfur) 0.52 v '0. 31 sulfurized-Dipeiteue (35%Sulfur) 0.22

By replacing the basic barium salt of the diwaxalkylated benzenesulfonic. acid in the above example with the corresponding basicmagnesium salt substantially the same results are obtained. j r j,

As further illustrative of this invention the, following in a CRCDesignation I. -4-545 (described on page 1395 Lubricant Composition D IParis by Parts by weight weight Mineral Oil of Lubricating Viscosity.98. 98. 52 Basic Barium Salt of a Di-wax-alkylat ed Benrene SulfontcAcid (16.1% Barium; 3.87% Sulfur) 1. l9 ,0. 89 PhosphorizedandSulfurized-Pinene (7.7%

Phosphorus, 21.3% Sulfur) 0. 63 0. 27 SulfurizedDipentene (35% Sulfur)0; 32

Table I Lubricant Lubricant G D Bearing Corrosion (mgs. weight loss inmetal per bearing) 81 69 Piston varnish rating (based on 8.9 9.1 Overallengine rating (based on 100) S6. 6 88. O

Lubricating Composition E F Parts by Paris by, 'weight weight MineralOil of Lubricating Viscosity 98.

Basic Barium Salt of a Di-wax-alkylated" 'Bo ene Sulfonic Acid (16.1%Barium;

3.87% Sulfur) .0. 84 'Phosphor'izedand Sulfurized-Pinene (7 .7%

, Phosphorus, 2i.3% Sulfur) Y O. 50 0.44 Sulfurized-Dipcntene (35%Sulfur) -4 0.13

Table II Lubricant E Lubricant F Time of Te t 240 hours 480 hours. No. lGroove (top ring). Moderate to heavy Moderate carbon 7 hard packeddeposit.v carbon deposit. No. z Groove Moderate to heavy Very'lightlacquer dark lacquer deposit over deposit plus some half of groove,carbon deposit. balance clean. No.13 Groove Moderate to heavy Stain onone half i dark lacquer of groove,

deposit over most balance clean. of groove. a

No. 4 Groove Light to moderate Clean.

dark lacquer deposit over most of groove.

Piston Skirt Trace of amber D0.

lacquer deposit on front side.

The oil-soluble sulfurized-monocyclic terpene hydrocarbons of thisinvention may be prepared by any of the well known methods forsulfurizing unsaturated hydro "'monocyclic terpene additives are thesulfurized-dipentenes "containing 3040% sulfur by weight, however, any

sulfurizecl monocyclic terpene containing about 24-60% by weight issatisfactory. Sulfurized-monocyclic terp'enes containing as little assulfur by weight are also contemplated.

The oil-soluble sulfurizedand phosphorized-dicyclic terpene hydrocarbonantioxidants ofthis invention are ithoseobtainedby reacting a dicyclicterpene hydrocarbon atoms.

suchas pinene, camphene, fenchene and similar terpencs possessing onedouble bond in the molecule and comprising two ring systems, with aphosphorus sufilde at a reaction temperature of about 100-160 C. Whileany phosphorus sulfide such as P 8 P 8 P 8 P 8 P 5 andthe like, may beemployed in the preparation of said reaction products, the preferredreaction products are those obtained employing phosphorus pentasulfide.While the proportions of these reactants will vary depending upon theoil-soluble and oil-improvement properties desired the preferred productis that obtained by the reaction of approximately onemolecular-proportion of a phosphorus sulfide, such as P S ,withapproximately four molecular proportions of a dicyclic terpene, such aspinene, at a reaction temperature of lO0-160 C.

The preferred oil-soluble metallo hydrocarbon sulfonatedetergent-dispersants of this invention are those obtained bysulfonatingwax-alkylated aromatic hydrocarbons and forming neutral orbasic metal salts thereof. This class may be represented by the generalformula where n is a whole number from 1 to 4, preferably 2,

where R is an aromatic hydrocarbon radical such as phenyl, tolyl, xylyl,cumyl, naphthyl, biphenyl, etc. where M is a bivalent metal such aszinc, the alkaline earth metals such as magnesium, calcium, strontium,barium, and the like, where X is SO R-(wax),, or preferably a hydroxylgroup. The Wax substituent or substituents of the preferreddetergent-dispersant of this invention consists of carbon andhydrocarbon as distinguished from ester waxes. The hydrocarbon waxsubstitucnt contains at least 18 carbon atoms in the lowest carbon chainand is derived from hydrocarbon waxes having melting points varyingbetween about 90 F. and about 180 F. The preferred wax substituents arethose known in the art as paraflin waxes which contain at least 20carbon atoms and usually not more than 30 and which have melting pointsvarying from 90 to 140 F. Other hydrocarbon wax substituents are thecerese waxes Which-have, melting points as high as 180 F. and arederived from petroleum. Other oil-soluble metallo alkylated arylsulfonate detergent-dispersants are also contemplated for example, thosearyl sulfonates containing alkyl groups possessing not less than eightcarbon Other typical oil-soluble hydrocarbon sulfonatedetergent-dispersants are those obtained by sulfonating paraffins,naphthenes the various parafiinic, naphthenic and aromatic petroleumfractions and the like, and forming the neutral metal or basic metalsalts thereof. As exemplary of the preferred detergent-dispersants arethe basic magnesium, neutral magnesium, basic calcium, neutral calcium,strontium, basic barium, and neutral barium salts of di-wax-alkylatedbenzene sulfonic acids. Other detergent-dispersants within the scope ofthis in oil sulfonate.

While the inventionjhas been described with respect to certain preferredembodiments it is not so limited in that various modifications may bemade which are obvious to those skilled in the art as for example theinclusion of stabilization agents, pour point depressants, extremepressure lubrication improving agents, viscosity improving agents, andthe like, without departing from the spirit or scope of the invention.

This application is a continuation-in-part of co-pending applicationSerial No. 208,054, filed January 26, 1951, now abandoned.

What is claimed is:

l. .A lubricating composition comprising a mineral oil and with respectto the mineral oil about 0.140% by weight of an oil-solublemetallo'hydroearbon sulfonate detergent, about 0.0$-3% by weight of anoil-soluble phosphorizedand sulfurized-dicyclic terpene, and about0.05-2% by weight of an oil-soluble sulfurized-monocyclic terpene.

2. A lubricating composition comprising a mineral oil fraction oflubricating viscosity and with respect to the mineral oil fraction about01-10% by weight of an oilsoluble metallo wax-alkylated aromatichydrocarbon sulfonate detergent, about 0.05-3% by weight of anoil-soluble phosphorizedand sulfurized-dicyclic terpene obtained byreacting a phosphorus sulfide with a dicyclic terpene, and about 0.05-2%by Weight of an oil-soluble sulfurized-monocyclic terpene containing24-50% sulfur by weight.

3. A lubricating composition comprising predominantly a mineral oilfraction of lubricating viscosity and with respect to the mineral oilfraction about 0.1% by weight of an oil-soluble basic bariumwax-alkylated aryl sulfonate detergent of the general formula where n isa whole number from l-3 inclusive and where R is a benzenoid hydrocarbonradical containing but one uncondensed benzene nucleus, about 0.05-3% byweight of a phosphorizedand sulfurized-dicyclic terpene obtained byreacting a phosphorus sulfide with a dicyclic terpene at about 100l60C., and about 0.052% by weight of a sulfurized-monocyclic terpenecontaining 30- 40% by weight sulfur.

4. A lubricating composition comprising predominantly a mineral oilfraction of lubricating viscosity and with respect to the mineral oilfraction about 0.1-10% by weight of an oil-soluble metallo wax-alkylatedaryl sulfonate detergent of the general formula Where n is a wholenumber from l-4, where R is an aromatic hydrocarbon radical, where M isa divalent metal, and where X is selected from the group consisting of ahydroxyl group and (wax),,-RSO about 0.05- 3% by weight of aphosphorizedand sulfurized-dicyclic terpene obtained by reacting aboutone molecular proportion of a phosphorus sulfide with about fourmolecular proportions of a dicyclic terpene at about 100-l60 C., andabout ODS-2% by weight of a sulfurized-monocyclic terpene containing30-40% by weight sulfur.

5. A lubricating composition comprising predominant- 1y a mineral oilfraction of. lubricating viscosity and with respect to the mineral oilfraction about 0.1-10% by weight of an oil-soluble metallo wax-alkylatedaryl sulfonate detergent of the general formula (wax) SOs-M-OH where Mis an alkaline earth metal, about 0.053% by weight of a phosphorizedandsulfurized-pinene obtained by reacting substantially one molecularproportion of phosphorus pentasulfide with substantially four molecularproportions of pinene at -l60 C., and about 0.05- 2% by weight of asulfurized-dipentene containing 30- 40% by weight sulfur.

7. A lubricating composition comprising predominantly a mineral oilfraction of lubricating viscosity and with respect to the mineral oilfraction about 0.4-5% by weight of an oil-soluble metallo wax-alkylatedaryl sulfonate detergent of the general formula (wax) 3 S 0 3 M where Mis an alkaline earth metal, about 0.1-1% by weight of a phosphorizedandsulfurized-pinene obtained by reacting substantially one molecularproportion of phosphorus pentasulfide with substantially four molecularproportions of pinene at l00-l60 C., and about 0.1- 0.5% by weight of asulfurized-dipentene containing 30- 40% by weight sulfur.

8. A' lubricating composition comprising predominantly a mineral oilfraction of lubricating viscosity and with respect to the mineral oilfraction about 0.45% by weight of an oil-soluble metallo wax-alkylatedaryl sulfonate detergent of the general formula (wa SOs-M-OH where M isan alkaline earth metal, about 0.1-1% by weight of a phosphorizedandsulfurized-pinene obtained by reacting substantially one molecularproportion of phosphorus pentasulfide with substantially four molecularproportions of pinene at 100-l60 C., and about 0.1- 05% by weight of asulfurized-dipentene containing 30- 40% by weight sulfur.

9. A lubricating composition comprising predominantly a mineral oilfraction of lubricating viscosity and with respect to the mineral oilfraction about 0.6-1.2% by weight of an oil-soluble metallo wax-alkylated aryl sulfonate detergent of the general formula (wax) 2 S0 Mwhere M is an alkaline earth metal, about 0.2-0.4% by Weight of aphosphorizedand sulfurized-pinene obtained by reacting substantially onemolecular proportion of phosphorus pentasulfide with substantially fourmolecular proportions of pinene at 100-160 C., and about 0.2- 0.4% byweight of a sulfurized-dipentene containing about 35% by weight sulfur.

10. A lubricating composition comprising predominantly a mineral oilfraction of lubricating viscosity and with respect to the mineral oilfraction about 0.6-1.2% by weight of an oil-soluble metallowax-alkylated aryl sulfonate detergent of the general formula where M isan alkaline earth metal, about 0.2-0.4% by weight of a phosphorizedandsulfurized-pinene obtained by reacting substantially one molecularproportion of phosphorus pentasulfide with substantially four moleculatproportions of pinene at l-l60 C., and about 02-04% by weight of asulfuriZed-dipentene containing about 35% by weight sulfur.

11. A lubricating composition comprising predominantly a mineral oilfraction of lubricating viscosity and with respect to the mineral oilfraction about 06-12% by weight of an oil-soluble barium wax-alkylatedaryl sulfonateof the general formula (wax) 2 S O 3 Ba about 0.2-0.4% byweight of a phosphorizedand sulfurized-pinene obtained by reactingsubstantially one molecular proportion of phosphorus pentasulfide withsubstantially four molecular proportions of pinene at 100-l60 C., andabout 02-04% by weight of a sulfurized-dipentene containing about 35% byweight sulfur.

12. A lubricating composition comprising predominantly a mineral oilfraction of lubricating viscosity and with respect to the mineral oilfraction about 06-12% by weight of an oil-soluble barium wax-alkylatedaryl sulfonate of the general formula about (ll-6.4% by weight of aphosphorizedand sulfurized-pinene obtained by reacting substantially onemolecular proportion of phosphorus pentasulfide with substantially fourmolecular proportions of pinene at l0O-l60 C., and about 02-04% byweight of a sulfurized-dipentene containing about 35% by weight sulfur.

13. A lubricating composition comprising predominantly a mineral oilfraction of lubricating viscosity and with respect to the mineral oilfraction about (lo-1.2% I

by weight of an oil-soluble magnesium wax-alkylated aryl sulfonate ofthe general formula where the wax substituent is derived from a parafiinwax containing 20-30 carbon atoms having a melting point of -140 F.,about 0.20.4% by weight of a phosphorizedand sulfuriZed-pinene obtainedby reacting substantially one molecular proportion of phosphoruspentasulfide with substantially four molecular proportions of pinene at-160 C., and about 02-04% by weight of a snfurized-dipentene containingabout 35% by weight sulfur.

References Cited in the file of this patent 1 UNITED STATES PATENTS2,417,305 Knowles Mar. 11, 1947 2,493,216 Berger Ian. 3, 1950 2,643,248Brennan June 23, 1953 2,721,862 Brennan Oct. 25, 1955

1. A LUBRICATING COMPOSITION COMPRISING A MINERAL OIL AND WITH RESPECTTO THE MINERAL OIL ABUT 0.1-10% BY WEIGHT OF AN OIL-SOLUBLE METALLOHYDROCARBON SULFONATE DETERGENT, ABOUT 0.05-3% BY WEIGHT OF ANOIL-SOLUBLE PHOSPHORIZED- AND SULFURIZED-DICYCLIC TERPENE, AND ABOUT0.05-2% BY WEIGHT OF AN OIL-SOLUBLE SULFURIZED-MONOCYCLIC TERPENE.